The present invention pertains to a lightweight lithium ion battery. In particular, it pertains to a compact lithium ion battery.
Lithium batteries are seen by many to be an attractive energy storage device. Lithium ion batteries have been targeted for various applications such as portable electronics, cellular phones, power tools, electric vehicles, and load-leveling/peak-shaving. The batteries are currently replacing many other traditional power sources such as lead acid batteries, nickel cadmium batteries, and nickel metal hydride batteries. Lithium ion batteries have been known for many years (see the Handbook of Batteries, David Linden, editor, second edition by McGraw-Hill, copyright 1995, in particular, chapters 36 and 39). Various aspects of lithium batteries have been described in a variety of U.S. Patents, such as U.S. Pat. No. 5,961,672 pertaining to a stabilized anode for lithium polymer batteries. U.S. Pat. No. 5,952,126 pertains to polymer solid electrolyte and lithium secondary cells. U.S. Pat. No. 5,900,183 pertains to polymer electrolytes as well as does U.S. Pat. No. 5,874,185. U.S. Pat. No. 5,849,434 describes non-aqueous electrolyte lithium secondary batteries. Other variations on lithium batteries are described in U.S. Pat. Nos. 5,853,914 and 5,773,959.
Appropriately packaging lithium ion batteries is particularly difficult in the automotive environment due to the need for corrosion resistance, crush and crash worthiness, and vibration resistance. The problems of such batteries can be characterized as a need for better seal robustness, namely overcome leak potential from internal pressure; better packaging robustness, namely better crush/crash worthiness; better thermal exchange properties, namely ability to dissipate heat and receive cooling more effectively; ease of processing and transitioning into mass production, that is, processes that lend themselves to automation.
It is an object of the present invention to provide a lithium ion battery wherein bipolar electrodes are utilized with a lithium ion permeable plastic separator there between, and the cell electrodes being electrically connected appropriately to the anode and cathode terminals which are at opposite ends of the housing for the battery.
Described is a substantially sealed lightweight lithium ion battery and container comprising:
a metallic housing having front and back segments, which segments are substantially equal in length and width and a pair of sides having a length substantially equal to the length of the front and back segments;
a lithium ion battery comprised of a stack of lithium ion electrodes sized to fit snuggly within the housing which battery has bipolar electrodes with an electrolyte there between;
a housing bottom member sized to snuggly fit the cathode terminal of the lithium ion electrode stack therein;
a housing top member sized to snuggly fit the anode terminal of the lithium stack therein; and
an insulated gasket between the anode and the metallic housing electrically separating the anode from the housing.